diff --git a/.github/workflows/documentation.yml b/.github/workflows/documentation.yml
new file mode 100644
index 0000000..ee89d54
--- /dev/null
+++ b/.github/workflows/documentation.yml
@@ -0,0 +1,24 @@
+name: Docs
+on: [push, pull_request, workflow_dispatch]
+permissions:
+    contents: write
+jobs:
+  docs:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-python@v3
+      - name: Install dependencies
+        run: |
+          pip install sphinx sphinx_rtd_theme mock
+      - name: Sphinx build
+        run: |
+          sphinx-build doc/source _build
+      - name: Deploy
+        uses: peaceiris/actions-gh-pages@v3
+        # if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/main' }}
+        with:
+          publish_branch: gh-pages
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_dir: _build/
+          force_orphan: true
\ No newline at end of file
diff --git a/aotools/functions/zernike.py b/aotools/functions/zernike.py
index 0eba058..719fafa 100644
--- a/aotools/functions/zernike.py
+++ b/aotools/functions/zernike.py
@@ -1,4 +1,5 @@
 import numpy
+import math
 from . import circle
 
 def phaseFromZernikes(zCoeffs, size, norm="noll", rot=0):
@@ -88,10 +89,10 @@ def zernikeRadialFunc(n, m, r):
     for i in range(0, int((n - m) / 2) + 1):
 
         R += numpy.array(r**(n - 2 * i) * (((-1)**(i)) *
-                         numpy.math.factorial(n - i)) /
-                         (numpy.math.factorial(i) *
-                          numpy.math.factorial(int(0.5 * (n + m) - i)) *
-                          numpy.math.factorial(int(0.5 * (n - m) - i))),
+                         math.factorial(n - i)) /
+                         (math.factorial(i) *
+                          math.factorial(int(0.5 * (n + m) - i)) *
+                          math.factorial(int(0.5 * (n - m) - i))),
                          dtype='float')
     return R
 
diff --git a/test/test_centroiders.py b/test/test_centroiders.py
index 8b066f6..a8fb3ab 100644
--- a/test/test_centroiders.py
+++ b/test/test_centroiders.py
@@ -1,5 +1,6 @@
 from aotools import image_processing
 import numpy
+# from nose.tools import raises
 
 
 def test_centre_of_gravity_single():
@@ -66,3 +67,13 @@ def test_correlation_many():
     com = image_processing.correlation_centroid(im, ref, 0.3)
     assert (com.shape[0] == 2)
     assert(com.shape[1] == 5)
+
+
+# @raises(ValueError)
+# def test_correlation_error():
+#     im = numpy.random.random((10))
+#     ref = numpy.random.random((10, 10))
+#     com = image_processing.correlation_centroid(im, ref, threshold=0.3)
+
+
+